In a press release issued late Saturday, the city of Bloomington utilities warned about a possible pink tint to the drinking water flowing out of the tap “in the coming days.”
The water does not pose a threat to human health, according to the news release, and the Indiana Department of Environmental Management (IDEM) has been notified of the incident.
The press release recommends that if your water appears to be tinted pink, you should postpone washing clothes until the water has cleared.
How long will that take?
The press release says it could take “several days” for the affected water to move through the city’s distribution system, from south to north. But once the pink water hits a particular faucet, it should not persist longer than several hours up to a day, according to the release.
The incident involved a pump that controls the feed of sodium permanganate, chemical used in water treatment. The pump malfunctioned and caused too much sodium permanganate to be fed into the water, the press release says.
According to the press release the pump malfunctioned during a period of low demand, a time when treatment operators will shut off parts of the plant for routine maintenance.
Has demand been especially low in recent weeks?
Based on the daily data on water pumped from Lake Monroe to the treatment facility, demand this March is somewhat lower than January and February, but has not been dramatically lower than in previous years during March. That is, through March, the COVID-19 epidemic doesn’t seem discernible in the water data.
The amount of water pumped during the month of March looks like it will typically dip for several days, likely due to the university’s spring break.
This year, the amount of water pumped dropped off for the last half of the month. That still put numbers for this March (456 million gallons) right around the average for the last four years, which is 454 million gallons.
Since 2010 the maximum amount of water pumped from the intake tower on a given day came in the drought year of 2012, when 26.08 million gallons were pumped on July 6 that year.